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figlet/inflate.c
Claudio Matsuoka 9b6d83988d Relicense zipio files under the MIT license 
Zipio files were licensed under a restrictive license containing a clause
mandating that any modifications to the source code must be sent via e-mail
to the copyright owner. The author was contacted and permitted the files
to be relicensed under the MIT license. This should avoid any problems
restributing FIGlet as free software in Linux distributions.

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
2011-01-11 13:26:08 -02:00

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/*
* inflate.c - inflate decompression routine
*
* Version 1.1.2
*/
/*
* Copyright (C) 1995, Edward B. Hamrick
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear in
* supporting documentation, and that the name of the copyright holders
* not be used in advertising or publicity pertaining to distribution of
* the software without specific, written prior permission. The copyright
* holders makes no representations about the suitability of this software
* for any purpose. It is provided "as is" without express or implied warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
* IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT
* OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
* USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
/*
* Changes from 1.1 to 1.1.2:
* Relicensed under the MIT license, with consent of the copyright holders.
* Claudio Matsuoka (Jan 11 2011)
*/
/*
* inflate.c is based on the public-domain (non-copyrighted) version
* written by Mark Adler, version c14o, 23 August 1994. It has been
* modified to be reentrant, more portable, and to be data driven.
*/
/*
* 1) All file i/o is done externally to these routines
* 2) Routines are symmetrical so inflate can feed into deflate
* 3) Routines can be easily integrated into wide range of applications
* 4) Routines are very portable, and use only ANSI C
* 5) No #defines in inflate.h to conflict with external #defines
* 6) No external routines need be called by these routines
* 7) Buffers are owned by the calling routine
* 8) No static non-constant variables are allowed
*/
/*
* Note that for each call to InflatePutBuffer, there will be
* 0 or more calls to (*putbuffer_ptr). Before InflatePutBuffer
* returns, it will have output as much uncompressed data as
* is possible.
*/
#ifdef MEMCPY
#include <mem.h>
#endif
#include "inflate.h"
/*
* Macros for constants
*/
#ifndef NULL
#define NULL ((void *) 0)
#endif
#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif
#ifndef WINDOWSIZE
#define WINDOWSIZE 0x8000
#endif
#ifndef WINDOWMASK
#define WINDOWMASK 0x7fff
#endif
#ifndef BUFFERSIZE
#define BUFFERSIZE 0x4000
#endif
#ifndef BUFFERMASK
#define BUFFERMASK 0x3fff
#endif
#ifndef INFLATESTATETYPE
#define INFLATESTATETYPE 0xabcdabcdL
#endif
/*
* typedefs
*/
typedef unsigned long ulg;
typedef unsigned short ush;
typedef unsigned char uch;
/* Structure to hold state for inflating zip files */
struct InflateState {
unsigned long runtimetypeid1; /* to detect run-time errors */
int errorencountered; /* error encountered flag */
/* Decoding state */
int state; /* -1 -> need block type */
/* 0 -> need stored setup */
/* 1 -> need fixed setup */
/* 2 -> need dynamic setup */
/* 10 -> need stored data */
/* 11 -> need fixed data */
/* 12 -> need dynamic data */
/* State for decoding fixed & dynamic data */
struct huft *tl; /* literal/length decoder tbl */
struct huft *td; /* distance decoder table */
int bl; /* bits decoded by tl */
int bd; /* bits decoded by td */
/* State for decoding stored data */
unsigned int storelength;
/* State to keep track that last block has been encountered */
int lastblock; /* current block is last */
/* Input buffer state (circular) */
ulg bb; /* input buffer bits */
unsigned int bk; /* input buffer count of bits */
unsigned int bp; /* input buffer pointer */
unsigned int bs; /* input buffer size */
unsigned char buffer[BUFFERSIZE]; /* input buffer data */
/* Storage for try/catch */
ulg catch_bb; /* bit buffer */
unsigned int catch_bk; /* bits in bit buffer */
unsigned int catch_bp; /* buffer pointer */
unsigned int catch_bs; /* buffer size */
/* Output window state (circular) */
unsigned int wp; /* output window pointer */
unsigned int wf; /* output window flush-from */
unsigned char window[WINDOWSIZE]; /* output window data */
/* Application state */
void *AppState; /* opaque ptr for callout */
/* pointers to call-outs */
int (*putbuffer_ptr)( /* returns 0 on success */
void *AppState, /* opaque ptr from Initialize */
unsigned char *buffer, /* buffer to put */
long length /* length of buffer */
);
void *(*malloc_ptr)(long length); /* utility routine */
void (*free_ptr)(void *buffer); /* utility routine */
unsigned long runtimetypeid2; /* to detect run-time errors */
};
/*
* Error handling macro
*/
#define ERROREXIT(is) {(is)->errorencountered = TRUE; return TRUE;}
/*
* Macros for handling data in the input buffer
*
* Note that the NEEDBITS and DUMPBITS macros
* need to be bracketed by the TRY/CATCH macros
*
* The usage is:
*
* TRY
* {
* NEEDBITS(j)
* x = b & mask_bits[j];
* DUMPBITS(j)
* }
* CATCH_BEGIN
* cleanup code
* CATCH_END
*
* Note that there can only be one TRY/CATCH pair per routine
* because of the use of goto in the implementation of the macros.
*
* NEEDBITS makes sure that b has at least j bits in it, and
* DUMPBITS removes the bits from b. The macros use the variable k
* for the number of bits in b. Normally, b and k are register
* variables for speed, and are initialized at the beginning of a
* routine that uses these macros from a global bit buffer and count.
*
* In order to not ask for more bits than there are in the compressed
* stream, the Huffman tables are constructed to only ask for just
* enough bits to make up the end-of-block code (value 256). Then no
* bytes need to be "returned" to the buffer at the end of the last
* block. See the huft_build() routine.
*/
#define TRY \
is->catch_bb = b; \
is->catch_bk = k; \
is->catch_bp = is->bp; \
is->catch_bs = is->bs;
#define CATCH_BEGIN \
goto cleanup_done; \
cleanup: \
b = is->catch_bb; \
k = is->catch_bk; \
is->bb = b; \
is->bk = k; \
is->bp = is->catch_bp; \
is->bs = is->catch_bs;
#define CATCH_END \
cleanup_done: ;
#define NEEDBITS(n) \
{ \
while (k < (n)) \
{ \
if (is->bs <= 0) \
{ \
goto cleanup; \
} \
b |= ((ulg) (is->buffer[is->bp & BUFFERMASK])) << k; \
is->bs--; \
is->bp++; \
k += 8; \
} \
}
#define DUMPBITS(n) \
{ \
b >>= (n); \
k -= (n); \
}
/*
* Macro for flushing the output window to the putbuffer callout.
*
* Note that the window is always flushed when it fills to 32K,
* and before returning to the application.
*/
#define FLUSHWINDOW(w, now) \
if ((now && (is->wp > is->wf)) || ((w) >= WINDOWSIZE)) \
{ \
is->wp = (w); \
if ((*(is->putbuffer_ptr)) \
(is->AppState, is->window+is->wf, is->wp-is->wf)) \
ERROREXIT(is); \
is->wp &= WINDOWMASK; \
is->wf = is->wp; \
(w) = is->wp; \
}
/*
* Inflate deflated (PKZIP's method 8 compressed) data. The compression
* method searches for as much of the current string of bytes (up to a
* length of 258) in the previous 32K bytes. If it doesn't find any
* matches (of at least length 3), it codes the next byte. Otherwise, it
* codes the length of the matched string and its distance backwards from
* the current position. There is a single Huffman code that codes both
* single bytes (called "literals") and match lengths. A second Huffman
* code codes the distance information, which follows a length code. Each
* length or distance code actually represents a base value and a number
* of "extra" (sometimes zero) bits to get to add to the base value. At
* the end of each deflated block is a special end-of-block (EOB) literal/
* length code. The decoding process is basically: get a literal/length
* code; if EOB then done; if a literal, emit the decoded byte; if a
* length then get the distance and emit the referred-to bytes from the
* sliding window of previously emitted data.
*
* There are (currently) three kinds of inflate blocks: stored, fixed, and
* dynamic. The compressor outputs a chunk of data at a time and decides
* which method to use on a chunk-by-chunk basis. A chunk might typically
* be 32K to 64K, uncompressed. If the chunk is uncompressible, then the
* "stored" method is used. In this case, the bytes are simply stored as
* is, eight bits per byte, with none of the above coding. The bytes are
* preceded by a count, since there is no longer an EOB code.
*
* If the data is compressible, then either the fixed or dynamic methods
* are used. In the dynamic method, the compressed data is preceded by
* an encoding of the literal/length and distance Huffman codes that are
* to be used to decode this block. The representation is itself Huffman
* coded, and so is preceded by a description of that code. These code
* descriptions take up a little space, and so for small blocks, there is
* a predefined set of codes, called the fixed codes. The fixed method is
* used if the block ends up smaller that way (usually for quite small
* chunks); otherwise the dynamic method is used. In the latter case, the
* codes are customized to the probabilities in the current block and so
* can code it much better than the pre-determined fixed codes can.
*
* The Huffman codes themselves are decoded using a mutli-level table
* lookup, in order to maximize the speed of decoding plus the speed of
* building the decoding tables. See the comments below that precede the
* lbits and dbits tuning parameters.
*/
/*
* Notes beyond the 1.93a appnote.txt:
*
* 1. Distance pointers never point before the beginning of the output
* stream.
* 2. Distance pointers can point back across blocks, up to 32k away.
* 3. There is an implied maximum of 7 bits for the bit length table and
* 15 bits for the actual data.
* 4. If only one code exists, then it is encoded using one bit. (Zero
* would be more efficient, but perhaps a little confusing.) If two
* codes exist, they are coded using one bit each (0 and 1).
* 5. There is no way of sending zero distance codes--a dummy must be
* sent if there are none. (History: a pre 2.0 version of PKZIP would
* store blocks with no distance codes, but this was discovered to be
* too harsh a criterion.) Valid only for 1.93a. 2.04c does allow
* zero distance codes, which is sent as one code of zero bits in
* length.
* 6. There are up to 286 literal/length codes. Code 256 represents the
* end-of-block. Note however that the static length tree defines
* 288 codes just to fill out the Huffman codes. Codes 286 and 287
* cannot be used though, since there is no length base or extra bits
* defined for them. Similarly, there are up to 30 distance codes.
* However, static trees define 32 codes (all 5 bits) to fill out the
* Huffman codes, but the last two had better not show up in the data.
* 7. Unzip can check dynamic Huffman blocks for complete code sets.
* The exception is that a single code would not be complete (see #4).
* 8. The five bits following the block type is really the number of
* literal codes sent minus 257.
* 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
* (1+6+6). Therefore, to output three times the length, you output
* three codes (1+1+1), whereas to output four times the same length,
* you only need two codes (1+3). Hmm.
*10. In the tree reconstruction algorithm, Code = Code + Increment
* only if BitLength(i) is not zero. (Pretty obvious.)
*11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19)
*12. Note: length code 284 can represent 227-258, but length code 285
* really is 258. The last length deserves its own, short code
* since it gets used a lot in very redundant files. The length
* 258 is special since 258 - 3 (the min match length) is 255.
*13. The literal/length and distance code bit lengths are read as a
* single stream of lengths. It is possible (and advantageous) for
* a repeat code (16, 17, or 18) to go across the boundary between
* the two sets of lengths.
*/
/*
* Huffman code lookup table entry--this entry is four bytes for machines
* that have 16-bit pointers (e.g. PC's in the small or medium model).
* Valid extra bits are 0..13. e == 15 is EOB (end of block), e == 16
* means that v is a literal, 16 < e < 32 means that v is a pointer to
* the next table, which codes e - 16 bits, and lastly e == 99 indicates
* an unused code. If a code with e == 99 is looked up, this implies an
* error in the data.
*/
struct huft {
uch e; /* number of extra bits or operation */
uch b; /* number of bits in this code or subcode */
union {
ush n; /* literal, length base, or distance base */
struct huft *t; /* pointer to next level of table */
} v;
};
/*
* Tables for deflate from PKZIP's appnote.txt.
*/
static const unsigned border[] = { /* Order of the bit length code lengths */
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
static const ush cplens[] = { /* Copy lengths for literal codes 257..285 */
3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
/* note: see note #13 above about the 258 in this list. */
static const ush cplext[] = { /* Extra bits for literal codes 257..285 */
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */
static const ush cpdist[] = { /* Copy offsets for distance codes 0..29 */
1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
8193, 12289, 16385, 24577};
static const ush cpdext[] = { /* Extra bits for distance codes */
0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
12, 12, 13, 13};
/*
* Constants for run-time computation of mask
*/
static const ush mask_bits[] = {
0x0000,
0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
};
/*
* Huffman code decoding is performed using a multi-level table lookup.
* The fastest way to decode is to simply build a lookup table whose
* size is determined by the longest code. However, the time it takes
* to build this table can also be a factor if the data being decoded
* is not very long. The most common codes are necessarily the
* shortest codes, so those codes dominate the decoding time, and hence
* the speed. The idea is you can have a shorter table that decodes the
* shorter, more probable codes, and then point to subsidiary tables for
* the longer codes. The time it costs to decode the longer codes is
* then traded against the time it takes to make longer tables.
*
* This results of this trade are in the variables lbits and dbits
* below. lbits is the number of bits the first level table for literal/
* length codes can decode in one step, and dbits is the same thing for
* the distance codes. Subsequent tables are also less than or equal to
* those sizes. These values may be adjusted either when all of the
* codes are shorter than that, in which case the longest code length in
* bits is used, or when the shortest code is *longer* than the requested
* table size, in which case the length of the shortest code in bits is
* used.
*
* There are two different values for the two tables, since they code a
* different number of possibilities each. The literal/length table
* codes 286 possible values, or in a flat code, a little over eight
* bits. The distance table codes 30 possible values, or a little less
* than five bits, flat. The optimum values for speed end up being
* about one bit more than those, so lbits is 8+1 and dbits is 5+1.
* The optimum values may differ though from machine to machine, and
* possibly even between compilers. Your mileage may vary.
*/
static const int lbits = 9; /* bits in base literal/length lookup table */
static const int dbits = 6; /* bits in base distance lookup table */
/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
#define BMAX 16 /* maximum bit length of any code (16 for explode) */
#define N_MAX 288 /* maximum number of codes in any set */
/*
* Free the malloc'ed tables built by huft_build(), which makes a linked
* list of the tables it made, with the links in a dummy first entry of
* each table.
*/
static int huft_free(
struct InflateState *is, /* Inflate state */
struct huft *t /* table to free */
)
{
struct huft *p, *q;
/* Go through linked list, freeing from the malloced (t[-1]) address. */
p = t;
while (p != (struct huft *)NULL)
{
q = (--p)->v.t;
(*is->free_ptr)((char*)p);
p = q;
}
return 0;
}
/*
* Given a list of code lengths and a maximum table size, make a set of
* tables to decode that set of codes. Return zero on success, one if
* the given code set is incomplete (the tables are still built in this
* case), two if the input is invalid (all zero length codes or an
* oversubscribed set of lengths), and three if not enough memory.
* The code with value 256 is special, and the tables are constructed
* so that no bits beyond that code are fetched when that code is
* decoded.
*/
static int huft_build(
struct InflateState *is, /* Inflate state */
unsigned *b, /* code lengths in bits (all assumed <= BMAX) */
unsigned n, /* number of codes (assumed <= N_MAX) */
unsigned s, /* number of simple-valued codes (0..s-1) */
const ush *d, /* list of base values for non-simple codes */
const ush *e, /* list of extra bits for non-simple codes */
struct huft **t, /* result: starting table */
int *m /* maximum lookup bits, returns actual */
)
{
unsigned a; /* counter for codes of length k */
unsigned c[BMAX+1]; /* bit length count table */
unsigned el; /* length of EOB code (value 256) */
unsigned f; /* i repeats in table every f entries */
int g; /* maximum code length */
int h; /* table level */
unsigned i; /* counter, current code */
unsigned j; /* counter */
int k; /* number of bits in current code */
int lx[BMAX+1]; /* memory for l[-1..BMAX-1] */
int *l = lx+1; /* stack of bits per table */
unsigned *p; /* pointer into c[], b[], or v[] */
struct huft *q; /* points to current table */
struct huft r; /* table entry for structure assignment */
struct huft *u[BMAX]; /* table stack */
unsigned v[N_MAX]; /* values in order of bit length */
int w; /* bits before this table == (l * h) */
unsigned x[BMAX+1]; /* bit offsets, then code stack */
unsigned *xp; /* pointer into x */
int y; /* number of dummy codes added */
unsigned z; /* number of entries in current table */
/* clear the bit length count table */
for (i=0; i<(BMAX+1); i++)
{
c[i] = 0;
}
/* Generate counts for each bit length */
el = n > 256 ? b[256] : BMAX; /* set length of EOB code, if any */
p = b; i = n;
do {
c[*p]++; p++; /* assume all entries <= BMAX */
} while (--i);
if (c[0] == n) /* null input--all zero length codes */
{
*t = (struct huft *)NULL;
*m = 0;
return 0;
}
/* Find minimum and maximum length, bound *m by those */
for (j = 1; j <= BMAX; j++)
if (c[j])
break;
k = j; /* minimum code length */
if ((unsigned)*m < j)
*m = j;
for (i = BMAX; i; i--)
if (c[i])
break;
g = i; /* maximum code length */
if ((unsigned)*m > i)
*m = i;
/* Adjust last length count to fill out codes, if needed */
for (y = 1 << j; j < i; j++, y <<= 1)
if ((y -= c[j]) < 0)
return 2; /* bad input: more codes than bits */
if ((y -= c[i]) < 0)
return 2;
c[i] += y;
/* Generate starting offsets into the value table for each length */
x[1] = j = 0;
p = c + 1; xp = x + 2;
while (--i) { /* note that i == g from above */
*xp++ = (j += *p++);
}
/* Make a table of values in order of bit lengths */
p = b; i = 0;
do {
if ((j = *p++) != 0)
v[x[j]++] = i;
} while (++i < n);
/* Generate the Huffman codes and for each, make the table entries */
x[0] = i = 0; /* first Huffman code is zero */
p = v; /* grab values in bit order */
h = -1; /* no tables yet--level -1 */
w = l[-1] = 0; /* no bits decoded yet */
u[0] = (struct huft *)NULL; /* just to keep compilers happy */
q = (struct huft *)NULL; /* ditto */
z = 0; /* ditto */
/* go through the bit lengths (k already is bits in shortest code) */
for (; k <= g; k++)
{
a = c[k];
while (a--)
{
/* here i is the Huffman code of length k bits for value *p */
/* make tables up to required level */
while (k > w + l[h])
{
w += l[h++]; /* add bits already decoded */
/* compute minimum size table less than or equal to *m bits */
z = (z = g - w) > (unsigned)*m ? *m : z; /* upper limit */
if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */
{ /* too few codes for k-w bit table */
f -= a + 1; /* deduct codes from patterns left */
xp = c + k;
while (++j < z) /* try smaller tables up to z bits */
{
if ((f <<= 1) <= *++xp)
break; /* enough codes to use up j bits */
f -= *xp; /* else deduct codes from patterns */
}
}
if ((unsigned)w + j > el && (unsigned)w < el)
j = el - w; /* make EOB code end at table */
z = 1 << j; /* table entries for j-bit table */
l[h] = j; /* set table size in stack */
/* allocate and link in new table */
if ((q = (struct huft *)
((*is->malloc_ptr)((z + 1)*sizeof(struct huft)))) ==
(struct huft *)NULL)
{
if (h)
huft_free(is, u[0]);
return 3; /* not enough memory */
}
*t = q + 1; /* link to list for huft_free() */
*(t = &(q->v.t)) = (struct huft *)NULL;
u[h] = ++q; /* table starts after link */
/* connect to last table, if there is one */
if (h)
{
x[h] = i; /* save pattern for backing up */
r.b = (uch)l[h-1]; /* bits to dump before this table */
r.e = (uch)(16 + j); /* bits in this table */
r.v.t = q; /* pointer to this table */
j = (i & ((1 << w) - 1)) >> (w - l[h-1]);
u[h-1][j] = r; /* connect to last table */
}
}
/* set up table entry in r */
r.b = (uch)(k - w);
if (p >= v + n)
r.e = 99; /* out of values--invalid code */
else if (*p < s)
{
r.e = (uch)(*p < 256 ? 16 : 15); /* 256 is end-of-block code */
r.v.n = (ush) *p++; /* simple code is just the value */
}
else
{
r.e = (uch)e[*p - s]; /* non-simple--look up in lists */
r.v.n = d[*p++ - s];
}
/* fill code-like entries with r */
f = 1 << (k - w);
for (j = i >> w; j < z; j += f)
q[j] = r;
/* backwards increment the k-bit code i */
for (j = 1 << (k - 1); i & j; j >>= 1)
i ^= j;
i ^= j;
/* backup over finished tables */
while ((i & ((1 << w) - 1)) != x[h])
w -= l[--h]; /* don't need to update q */
}
}
/* return actual size of base table */
*m = l[0];
/* Return true (1) if we were given an incomplete table */
return y != 0 && g != 1;
}
/*
* inflate (decompress) the codes in a stored (uncompressed) block.
* Return an error code or zero if it all goes ok.
*/
static int inflate_stored(
struct InflateState *is /* Inflate state */
)
{
ulg b; /* bit buffer */
unsigned k; /* number of bits in bit buffer */
unsigned w; /* current window position */
/* make local copies of state */
b = is->bb; /* initialize bit buffer */
k = is->bk; /* initialize bit count */
w = is->wp; /* initialize window position */
/*
* Note that this code knows that NEEDBITS jumps to cleanup
*/
while (is->storelength > 0) /* do until end of block */
{
NEEDBITS(8)
is->window[w++] = (uch) b;
DUMPBITS(8)
FLUSHWINDOW(w, FALSE);
is->storelength--;
}
cleanup:
/* restore the state from the locals */
is->bb = b; /* restore bit buffer */
is->bk = k; /* restore bit count */
is->wp = w; /* restore window pointer */
if (is->storelength > 0)
return -1;
else
return 0;
}
static int inflate_codes(
struct InflateState *is, /* Inflate state */
struct huft *tl, /* literal/length decoder table */
struct huft *td, /* distance decoder table */
int bl, /* number of bits decoded by tl[] */
int bd /* number of bits decoded by td[] */
)
{
unsigned e; /* table entry flag/number of extra bits */
unsigned n, d; /* length and index for copy */
unsigned w; /* current window position */
struct huft *t; /* pointer to table entry */
unsigned ml, md; /* masks for bl and bd bits */
ulg b; /* bit buffer */
unsigned k; /* number of bits in bit buffer */
/* make local copies of state */
b = is->bb; /* initialize bit buffer */
k = is->bk; /* initialize bit count */
w = is->wp; /* initialize window position */
/* inflate the coded data */
ml = mask_bits[bl]; /* precompute masks for speed */
md = mask_bits[bd];
for (;;) /* do until end of block */
{
TRY
{
NEEDBITS((unsigned)bl)
if ((e = (t = tl + ((unsigned)b & ml))->e) > 16)
do {
if (e == 99)
return 1;
DUMPBITS(t->b)
e -= 16;
NEEDBITS(e)
} while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
DUMPBITS(t->b)
if (e == 16) /* it's a literal */
{
is->window[w++] = (uch)t->v.n;
FLUSHWINDOW(w, FALSE);
}
else if (e == 15) /* it's an EOB */
{
break;
}
else /* it's a length */
{
/* get length of block to copy */
NEEDBITS(e)
n = t->v.n + ((unsigned)b & mask_bits[e]);
DUMPBITS(e);
/* decode distance of block to copy */
NEEDBITS((unsigned)bd)
if ((e = (t = td + ((unsigned)b & md))->e) > 16)
do {
if (e == 99)
return 1;
DUMPBITS(t->b)
e -= 16;
NEEDBITS(e)
} while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
DUMPBITS(t->b)
NEEDBITS(e)
d = w - t->v.n - ((unsigned)b & mask_bits[e]);
DUMPBITS(e)
/* do the copy */
do {
n -= (e = ((e = WINDOWSIZE - ((d &= WINDOWMASK) > w ? d : w)) > n)
? n : e
);
#if defined(MEMCPY)
if (w - d >= e) /* (this test assumes unsigned comparison) */
{
memcpy(is->window + w, is->window + d, e);
w += e;
d += e;
}
else /* do it slow to avoid memcpy() overlap */
#endif /* MEMCPY */
do {
is->window[w++] = is->window[d++];
} while (--e);
FLUSHWINDOW(w, FALSE);
} while (n);
}
}
CATCH_BEGIN
is->wp = w; /* restore window pointer */
return -1;
CATCH_END
}
/* restore the state from the locals */
is->bb = b; /* restore bit buffer */
is->bk = k; /* restore bit count */
is->wp = w; /* restore window pointer */
/* done */
return 0;
}
/*
* "decompress" an inflated type 0 (stored) block.
*/
static int inflate_stored_setup(
struct InflateState *is /* Inflate state */
)
{
unsigned n; /* number of bytes in block */
ulg b; /* bit buffer */
unsigned k; /* number of bits in bit buffer */
/* make local copies of state */
b = is->bb; /* initialize bit buffer */
k = is->bk; /* initialize bit count */
TRY
{
/* go to byte boundary */
n = k & 7;
DUMPBITS(n);
/* get the length and its complement */
NEEDBITS(16)
n = ((unsigned)b & 0xffff);
DUMPBITS(16)
NEEDBITS(16)
if (n != (unsigned)((~b) & 0xffff))
return 1; /* error in compressed data */
DUMPBITS(16)
}
CATCH_BEGIN
return -1;
CATCH_END
/* Save store state for this block */
is->storelength = n;
/* restore the state from the locals */
is->bb = b; /* restore bit buffer */
is->bk = k; /* restore bit count */
return 0;
}
/*
* decompress an inflated type 1 (fixed Huffman codes) block. We should
* either replace this with a custom decoder, or at least precompute the
* Huffman tables.
*/
static int inflate_fixed_setup(
struct InflateState *is /* Inflate state */
)
{
int i; /* temporary variable */
struct huft *tl; /* literal/length code table */
struct huft *td; /* distance code table */
int bl; /* lookup bits for tl */
int bd; /* lookup bits for td */
unsigned l[288]; /* length list for huft_build */
/* set up literal table */
for (i = 0; i < 144; i++)
l[i] = 8;
for (; i < 256; i++)
l[i] = 9;
for (; i < 280; i++)
l[i] = 7;
for (; i < 288; i++) /* make a complete, but wrong code set */
l[i] = 8;
bl = 7;
if ((i = huft_build(is, l, 288, 257, cplens, cplext, &tl, &bl)) != 0)
return i;
/* set up distance table */
for (i = 0; i < 30; i++) /* make an incomplete code set */
l[i] = 5;
bd = 5;
if ((i = huft_build(is, l, 30, 0, cpdist, cpdext, &td, &bd)) > 1)
{
huft_free(is, tl);
return i;
}
/* Save inflate state for this block */
is->tl = tl;
is->td = td;
is->bl = bl;
is->bd = bd;
return 0;
}
/*
* decompress an inflated type 2 (dynamic Huffman codes) block.
*/
#define PKZIP_BUG_WORKAROUND
static int inflate_dynamic_setup(
struct InflateState *is /* Inflate state */
)
{
int i; /* temporary variables */
unsigned j;
unsigned l; /* last length */
unsigned m; /* mask for bit lengths table */
unsigned n; /* number of lengths to get */
struct huft *tl; /* literal/length code table */
struct huft *td; /* distance code table */
int bl; /* lookup bits for tl */
int bd; /* lookup bits for td */
unsigned nb; /* number of bit length codes */
unsigned nl; /* number of literal/length codes */
unsigned nd; /* number of distance codes */
#ifdef PKZIP_BUG_WORKAROUND
unsigned ll[288+32]; /* literal/length and distance code lengths */
#else
unsigned ll[286+30]; /* literal/length and distance code lengths */
#endif
ulg b; /* bit buffer */
unsigned k; /* number of bits in bit buffer */
/* make local copies of state */
b = is->bb; /* initialize bit buffer */
k = is->bk; /* initialize bit count */
/* initialize tl for cleanup */
tl = NULL;
TRY
{
/* read in table lengths */
NEEDBITS(5)
nl = 257 + ((unsigned)b & 0x1f); /* number of literal/length codes */
DUMPBITS(5)
NEEDBITS(5)
nd = 1 + ((unsigned)b & 0x1f); /* number of distance codes */
DUMPBITS(5)
NEEDBITS(4)
nb = 4 + ((unsigned)b & 0xf); /* number of bit length codes */
DUMPBITS(4)
#ifdef PKZIP_BUG_WORKAROUND
if (nl > 288 || nd > 32)
#else
if (nl > 286 || nd > 30)
#endif
return 1; /* bad lengths */
/* read in bit-length-code lengths */
for (j = 0; j < 19; j++) ll[j] = 0;
for (j = 0; j < nb; j++)
{
NEEDBITS(3)
ll[border[j]] = (unsigned)b & 7;
DUMPBITS(3)
}
/* build decoding table for trees--single level, 7 bit lookup */
bl = 7;
if ((i = huft_build(is, ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
{
if (i == 1)
huft_free(is, tl);
return i; /* incomplete code set */
}
/* read in literal and distance code lengths */
n = nl + nd;
m = mask_bits[bl];
i = l = 0;
while ((unsigned)i < n)
{
NEEDBITS((unsigned)bl)
j = (td = tl + ((unsigned)b & m))->b;
DUMPBITS(j)
j = td->v.n;
if (j < 16) /* length of code in bits (0..15) */
ll[i++] = l = j; /* save last length in l */
else if (j == 16) /* repeat last length 3 to 6 times */
{
NEEDBITS(2)
j = 3 + ((unsigned)b & 3);
DUMPBITS(2)
if ((unsigned)i + j > n)
return 1;
while (j--)
ll[i++] = l;
}
else if (j == 17) /* 3 to 10 zero length codes */
{
NEEDBITS(3)
j = 3 + ((unsigned)b & 7);
DUMPBITS(3)
if ((unsigned)i + j > n)
return 1;
while (j--)
ll[i++] = 0;
l = 0;
}
else /* j == 18: 11 to 138 zero length codes */
{
NEEDBITS(7)
j = 11 + ((unsigned)b & 0x7f);
DUMPBITS(7)
if ((unsigned)i + j > n)
return 1;
while (j--)
ll[i++] = 0;
l = 0;
}
}
/* free decoding table for trees */
huft_free(is, tl);
}
CATCH_BEGIN
if (tl) huft_free(is, tl);
return -1;
CATCH_END
/* restore the state from the locals */
is->bb = b; /* restore bit buffer */
is->bk = k; /* restore bit count */
/* build the decoding tables for literal/length and distance codes */
bl = lbits;
if ((i = huft_build(is, ll, nl, 257, cplens, cplext, &tl, &bl)) != 0)
{
if (i == 1) {
/* incomplete literal tree */
huft_free(is, tl);
}
return i; /* incomplete code set */
}
bd = dbits;
if ((i = huft_build(is, ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0)
{
if (i == 1) {
/* incomplete distance tree */
#ifdef PKZIP_BUG_WORKAROUND
}
#else
huft_free(is, td);
}
huft_free(is, tl);
return i; /* incomplete code set */
#endif
}
/* Save inflate state for this block */
is->tl = tl;
is->td = td;
is->bl = bl;
is->bd = bd;
return 0;
}
/* Routine to initialize inflate decompression */
void *InflateInitialize( /* returns InflateState */
void *AppState, /* for passing to putbuffer */
int (*putbuffer_ptr)( /* returns 0 on success */
void *AppState, /* opaque ptr from Initialize */
unsigned char *buffer, /* buffer to put */
long length /* length of buffer */
),
void *(*malloc_ptr)(long length), /* utility routine */
void (*free_ptr)(void *buffer) /* utility routine */
)
{
struct InflateState *is;
/* Do some argument checking */
if ((!putbuffer_ptr) || (!malloc_ptr) || (!free_ptr)) return NULL;
/* Allocate the InflateState memory area */
is = (struct InflateState *) (*malloc_ptr)(sizeof(struct InflateState));
if (!is) return NULL;
/* Set up the initial values of the inflate state */
is->runtimetypeid1 = INFLATESTATETYPE;
is->errorencountered = FALSE;
is->bb = 0;
is->bk = 0;
is->bp = 0;
is->bs = 0;
is->wp = 0;
is->wf = 0;
is->state = -1;
is->lastblock = FALSE;
is->AppState = AppState;
is->putbuffer_ptr = putbuffer_ptr;
is->malloc_ptr = malloc_ptr;
is->free_ptr = free_ptr;
is->runtimetypeid2 = INFLATESTATETYPE;
/* Return this state info to the caller */
return is;
}
/* Call-in routine to put a buffer into inflate decompression */
int InflatePutBuffer( /* returns 0 on success */
void *InflateState, /* opaque ptr from Initialize */
unsigned char *buffer, /* buffer to put */
long length /* length of buffer */
)
{
struct InflateState *is;
int beginstate;
/* Get (and check) the InflateState structure */
is = (struct InflateState *) InflateState;
if (!is || (is->runtimetypeid1 != INFLATESTATETYPE)
|| (is->runtimetypeid2 != INFLATESTATETYPE)) return TRUE;
if (is->errorencountered) return TRUE;
do
{
int size, i;
if ((is->state == -1) && (is->lastblock)) break;
/* Save the beginning state */
beginstate = is->state;
/* Push as much as possible into input buffer */
size = BUFFERSIZE - is->bs;
if (size > length) size = (int) length;
i = is->bp + is->bs;
while (size-- > 0)
{
is->buffer[i++ & BUFFERMASK] = *buffer;
is->bs++;
buffer++;
length--;
}
/* Process some more data */
if (is->state == -1)
{
int e; /* last block flag */
unsigned t; /* block type */
ulg b; /* bit buffer */
unsigned k; /* number of bits in bit buffer */
/* make local copies of state */
b = is->bb; /* initialize bit buffer */
k = is->bk; /* initialize bit count */
TRY
{
/* read in last block bit */
NEEDBITS(1)
e = (int)b & 1;
DUMPBITS(1)
/* read in block type */
NEEDBITS(2)
t = (unsigned)b & 3;
DUMPBITS(2)
if (t <= 2)
{
is->state = t;
is->lastblock = e;
}
else
{
ERROREXIT(is);
}
}
CATCH_BEGIN
CATCH_END
/* restore the state from the locals */
is->bb = b; /* restore bit buffer */
is->bk = k; /* restore bit count */
}
else if (is->state == 0)
{
int ret;
ret = inflate_stored_setup(is);
if (ret > 0)
ERROREXIT(is);
if (ret == 0) is->state += 10;
}
else if (is->state == 1)
{
int ret;
ret = inflate_fixed_setup(is);
if (ret > 0)
ERROREXIT(is);
if (ret == 0) is->state += 10;
}
else if (is->state == 2)
{
int ret;
ret = inflate_dynamic_setup(is);
if (ret > 0)
ERROREXIT(is);
if (ret == 0) is->state += 10;
}
else if (is->state == 10)
{
int ret;
ret = inflate_stored(is);
if (ret > 0)
ERROREXIT(is);
if (ret == 0)
{
is->state = -1;
}
}
else if ((is->state == 11) ||
(is->state == 12) )
{
int ret;
ret = inflate_codes(is, is->tl, is->td, is->bl, is->bd);
if (ret > 0)
ERROREXIT(is);
if (ret == 0)
{
/* free the decoding tables */
huft_free(is, is->tl);
huft_free(is, is->td);
is->state = -1;
}
}
else
{
ERROREXIT(is);
}
}
while (length || (is->state != beginstate));
FLUSHWINDOW(is->wp, TRUE);
return is->errorencountered;
}
/* Routine to terminate inflate decompression */
int InflateTerminate( /* returns 0 on success */
void *InflateState /* opaque ptr from Initialize */
)
{
int err;
void (*free_ptr)(void *buffer);
struct InflateState *is;
/* Get (and check) the InflateState structure */
is = (struct InflateState *) InflateState;
if (!is || (is->runtimetypeid1 != INFLATESTATETYPE)
|| (is->runtimetypeid2 != INFLATESTATETYPE)) return TRUE;
/* save the error return */
err = is->errorencountered || (is->bs > 0)
|| (is->state != -1)
|| (!is->lastblock);
/* save the address of the free routine */
free_ptr = is->free_ptr;
/* Deallocate everything */
(*free_ptr)(is);
return err;
}
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